Recoil mechanism for guns



B. B. HOLMES.

RECOIL MECHANISM FOR GUNS.

APPLICATION FILED NOV. 22, 1919.

Patented Nov. 8, 1921.

.w ani .M E 0 j n ml J w@ 7 n .732@ 2 d 2 I i 5 BRADFORD E. rioni/TES, or THE UrnTEn STATES ARMY, ASSIGNOR To NEWTON D. BAKER, SECRETARY or Wan, UNITED STATES on AMERICA, TRUSTEE.

RECOEL MECHANISM FOR GUNS.

Leserin Speccation of Letters Patent.

Patented Nov. s, roei.

To all 'whom t may concern Be it known that l, BRADFORD B. HOLMES,

major, United vStates Army, a citizen of the United States, stationed at Washington, District of Columbia, have invented an lmprovement in Recoil Mechanism for Guns, of which the following is a specification.

The invention described herein may be used by the Government, or any of its officers or employees in prosecution of work for the Government, or by any other lperson in the United States, without payment yto me of any royalty thereon.

This invention relates to improvements in recoil mechanism for guns with special reference to .recoil mechanism employing a recuperator system of the hydropneumatic t e.

yllhe object of the invention is to provide a piston construction in the recuperator'cylinder for separating the gas and liquid in a simple and inexpensivermanner, by eliminating the necessity for the costly mounting and packing construction heretofore used.

Another object of the invention is to provide a structure which may be disassembled, to a large extent, in the'iield vwithout permitting the escape of gas or of all of the liquid, and without the usual precautions,

since the mechanism .itself is provided with safety means. l

Another object of they invention is to provide Vgas containing means with a safety valvewhich will be opened to permit the es-'I capeof gas under pressure upon undue leal;-

scription progresses.

Figure 1 is a perspective view of a gun and recoil mechanism of my invention in position on the gun carriage;

Fig. 2 is an end view partly in sectionvof the gun and recoil mechanism removed from the carriage;

Fig. 3 is a vertical B`B of F ig. 2;

Fin'. 4'is a horizontal section on the line A-' of Fig. 2; K

Fig. 5 is a vertical section Yon the line ffl-0, Fig. 3; and f i Fig. 6 is a vertical section on the line D-D of Figs. 3 and 4. i

section on the line The cradle 1 is mounted on the top carriage of the trail by means of trunnions 2. The cradle embodies the body of the recoil mechanism 3, in which is formed a recoil cylinder 4 and a recuperator cylinder 5. The gun 6 is mounted for longitudinal movement in the guide-rails 7 of the cradle. y

Wfithin therecoil cylinder 4 is the usual recoil piston 8 and piston rod 9, the said cylinder being closed at one end by the screw-plug 10 and the other end by suitable packing' 11 and screw-plug 12. Y

The gun 6 is secured to the piston-rod 9 by means of a recoil lug inthe usual manner so that on recoil of the gun, the pistonrod and piston move therewith. l

The recuperator cylinder 5 isv connected with the recoil cylinder 4 by means of a passageway 13, which is controlled-by a springpressed valve 19 urged to its seat by a spring 20.' Extending from proximity of the stem of the valve 19 is a valve follower 21, which projects into acasing 22 secured to the recuperator body. Belleville washers 26 are held in compression between a head 24l mounted on the 'valve follower and a collar 25 formed on the valve follower which abuts against a nut 25 for limiting the movementl of the valve follower in one direction. The

head 24 is retained on the valve follower by means of the nut 24. The nutk 25 retains the valve cage 19 in position.y The head 24 is movable longitudinally on the follower for the purpose of placing additional compression on the Belleville washers as will hereinafter be described.l f

v A variable recoil slide 27 is formed with a tapered or wedge shaped cam portion 28 which is adapted to act on'head 24 for increasing or decreasing the tension on Belleville washers 26 by forcing the head 24` to slide on the-valve follower. The slide 27 enssf . will hereinafter appear.

gages with a cam (not shown) on the trunnions 2 and as the gun moves in elevation or depression, the slide and cam 28 are correspondingly moved and act upon the head 24 so as to adjust the tension on the Belleville washers 26 and thus through the valve follower tend to hold the recoil valve 29 to its seat with a force depending for magnitude upon the position of the gun so that most of the energy of recoil is absorbed by the oil pushing valve 19 olf its seat against heavy spring pressure.

After passing the valve 19, theoil enters the space 30 in the recuperatorcylinder between a piston-head 31 and the rear end 32 of the recuperator cylinder. This end of the recuperatorcylinder is formed with a projecting annular lip 33 for a purpose which Within the rel;;uperator cylinder, rearward of the pistonhead 31 is a flexible metallic envelop 34 having convclutions forming in effect a bellows. by a piston-head, 36 having a central sleeve 37 closed at its forward end and extending into the bellows for the reception of a sleeve 38 projecting from piston-head 31 which slides in said sleeve 37 in a telescopic inanner. This sleeve is provided with a longitudinal groove 39 for engaging a pin 40 proj ecting from piston head 36, which restricts the sleeve from rotation with respect to said piston-head.

Inclosed in the telescoping sleeves and compressed, between the two piston-heads of the re'cuperator'4 cylinder is a spiral spring 41 secured at one end to the sleeve 37 of the piston-head 36 and at the other'end to the piston-head 31 by any suitable means such as a nutk 42, as shown in Fig. 4.

The piston head 31 is formed on its rearward surface with a groove 43 in which is inserted the annular packing 44. This annular packing is adapted to coperate with the projecting lip 33, as will hereinafter appear.

v The forward end of the recuperator cylinder is closed by means of an air-cap 45 held inplace against a shoulder 46 formed in the -interior Aof the recuperator cylinder by a retaining nut 47. The cap 45 has an inwardly extending iiange 48 to which is secured by means of screw threads, the rearward end i of 4the bellows 34. The cap 45 is centrally vscrews into the l)ylinder closure 45'.

boredvand in this opening Vis placed an air `perator bellows may be replenished through the valve 50.

The piston head 36 is formed with an aperture which is controlled by means of a valve 56 normally held to its seat by means The rear end of the bellows is closed of a spring compressed between the rearward face of the piston-head and a flange 57 formed on the end of the valve stem. This valve comprises a safety feature which is considered of the utmost importance.

The rearward end of the recuperator cylinder is closed by means of a plug 60 held in place by suitable packing, and the retaining nut 61. This plug is apertured so as to aline with passage 13 and contains the recoil valve 19 which has been previously-described. This plug also contains the radially extending counter-recoil passage 62 which is controlled by the check vvalve 63. The counter-recoil passage 62 radiates from the central opening l64, the forward end of which is partially closed by the apertured plug 65 through vwhich extends the tapered counter recoil buffer 66. The recoil buffer is secured to the piston-head 31 bymeans of the screw-threads 67 formed on the'annulai' flange of the base of the counter recoil buffer engaging corresponding threads on'a central annular flange 68 jof the pistonhead 31 forming in effect a housing for the spring retaining lnut 42. Also extending from the central aperture 64 isa radial drain passage.

7 0 normally closed by means of the `plug7 2.

It will be understood that on counterrecoil, 'the check valve 63 will be raised from its seat so that the oil may find its way through passage 62 and connecting passage 13 to the recoil cylinder.

vNear ,the end of the `counter-recoil the recoilV buffer 66 enters the central orifice urged forward by means of a spring81y of the Screw plug 65 thereby cutting down y the flow of oil and allowing the gun to go which is compressed between the flangeSO i and an aperture retaining nut 82 and packing 83. l Y f j l`he rod 7 8 is extended beyond the flange 8O and passes through the spring 81 and the packing 83 and retaining nutr82. This rod also extends'inward so as to contact with the piston-head 31`and is adapted to actas a telltale or signal.

An oil reservoir 85 is formed in therecuperator body by means of the bent plates 86, which are secured to Vthe recuperator body in any manner which will form a fluid tight joint. This reservoir communicateswith the inlet valve 88 of an oil pump 89 by means of annular passage 90. andv passage 91 through the recuperator body. The piston of the oil pump is indicated at 92 and oscillation of the handle 95 is continued until the telltale Aindicates a sucient supply of oil which in this case is when the rod 7T is flush with' the end of the` recuperator cylinder.

The recuperator cylinder is formed withV longitudinal grooves 102 in the vicinity of the normal position of the piston head 36 so as to permit oil to pass from one side to the other of said piston head.

rEhe operation of the device is as follows: On the recoil of the gun, the oil in the rear of the recoil piston is forced through passage 13 and valve 19 to the space 30 of the recuperator cylinder, the resistance of the passage to the oil depending upon the elevation of the gun in positioning the cam slide and head 24e of the valve follower.

rl`he oil entering the space 30 forces back the piston-heads 3i and 36 thereby compressing bellows 34: and the gas contained therein. As the bellows are compressed the oil contained in the convolutions is squeezed out and passes by means of grooves 102 into the space between the two pistons so that the piston head 36 will travel forward a little faster than the piston head 31. rllhe spring al, however, will tend to restore the two piston-heads to the same relatii/'ev position. l

r)The counter-recoil is effected by the eX- pansion of air within the bellows forcing the oil back to the recoil cylinder through the oriiice in plug 65, passages 64 and 62 Aand check valve 68 as previously described.

1n case of leakage of oil, by the blowing out of a packing or by long idleness, or other cause, the packing ring aa in piston head 31 is brought into contact with lip 83 by the pressure (about 1,200 pounds per square inch) of the air or other gas within the bellows behind it, thus forming a tight joint.

The oil in space 80 and around the bellows is therefore, trapped and cannot escape. It is only necessary, therefore, to repair the packing and pump in some more oil by means of oil pump 89. This feature enables the recoil rod, piston, oil pump, counter recoil system, recoil valve and the plug 60 to be disassembled in the held for repairs without permitting the escape of ln case oil within the space between the two pistons should leak out, the safety valve 56 coming in contact with piston head 31 will be forced open and the gas withinthe bellows `will be permitted to escape thus preventing the bellows from being blown up. AThis invention provides ya recoil mechanism of simple construction which can be continued in use for a long period of .time away from any source of supplies,'since the gas ofthe bellows will require slight replenishing and the oil maybe replenishedy from the reservoir 85 without further equipment. f p 1 The invention is also valuable because of the fact that practically all 4of the parts of the @un which are likely toy become out of order may be disassembled and repairedA in the iield without 'danger of injury either to the person making the repairs or to the mechanism.

Having thus described my invention, what 1 claim as new and desire to secure by Letters Patent, is z- 1. In a recoil mechanism for guns, a recuperator mechanism of the hydropneumatic type comprising spaced piston-heads, a spring compressed'between said piston heads and a valve extending through one of said piston-heads and adapted to be operated by contact with the other of said piston heads.

2. 1n a recoil mechanism of the class described, a recuperator cylinder, a closure for the same containing a recoil valve,.a

counter-recoil valve, an oil pump cylinder and piston, and a rod` extending through said closure for indicating the amount of oil contained in the recuperator cylinder.

3. In a recoil mechanism of the class described, a recuperator cylinder formed at one end with a projecting annular lip, a piston-head within said cylinder, an annular packing ring on said cylinder adapted to engage said lip upon the escape of oil from the recuperator cylinder thereby forming a seal forthe prevention of further leakage.l

4. In a recoil mechanism of the class described, a recuperator cylinder, a plurality of piston-heads slidably mounted therein, a bellows containing a fluid under pressure, an annular packing ring on the faceV of one of said piston-heads, and an annular lip on lthe cylindel1 for engaging said packing ring 6. In a recoil system, a recoil cylinder and piston therefor, a recuperator cylinder containing a liquid and a gas under pressure, a passage-Way connecting said cylinders, means for separating the liquid from the gas, a removable plug for closing one end of' said recupcrator cylinder and a safety device for releasing thev gas pressure upon excessive longitudinal movement of said means.

k7. In a recoil mechanism for guns, a recuperator mechanism of a hydropneumatic type, comprising an eXpansible container for iuid under pressure and an automatic safety means for relieving the fluid pressure.

8. In a recoil mechanism for` guns, a re-y cuperator cylinder, an vexpansible container for fluid under pressure located Within the cylinder and automatic means for relieving pressure in the container.

9. In a recoil mechanism, a recuperator cylinder, a piston in said cylinder, a removable plug for closing one end of said cylinder, a rod having an intermediate collar eX-` tending through said plug, a spring engaging said collar for yieldingly urging said rod into contact with saidy piston, said rod adapted to project beyond the plug to indicat-e the fluid contents of the cylinder.

vBRADFORD B. HOLMES. 

